Pharmacokinetics And Residues Of Poly I:C In Chicken

Polynucleotide (Poly I:C) is a copolymer of polyinosinic acid and polycytidylic acid. It is an efficient inducer of interferon (IFN) and plays a role on the broad-spectrum antivirus, promoting cell-mediated immune responses, enhancing phagocytosis and digestion of macrophage, stimulating the function and proliferation of T lymphocytes, activity of antineoplastic, antibacterium and antitozoon. Poly I:C has been used in human clinical medicine but not yet permitted in animal husbandry. Only a few Poly I:C reports about pharmacology, toxicology and its mechanism have been reported because its special structure and property which is different from normal pharmaceutical chemicals. The aim of this study is to evaluate the pharmacokinetics, and the residues of Poly I:C in the edible tissues of chickens.Pharmacokinetics and tissue distributions of Poly I:C in chickens To evaluate the pharmacokinetics and the tissue distributions of Poly I:C in chickens. The liquid scintillation counter was been used to determine Poly I:C concentrations in the plasma and the tissues of chickens at the selected time intervals after intramuscular injection of [3H]Poly I:C at a dose of0.01mg/kg. The3p97computer program was been used to analyze the pharmacokinetic model and calculate the pharmacokinetic parameters. The results showed that the plasma concentration of Poly I:C was characteristic of a two-compartment open model. The main pharmacokinetic variables were:T1/2α=1.438579±0.869301h, T1/2β=9.227321±0.706856h, AUC=0.070868±0.013235(μg/mL)*h, C(max)=0.007096±0.002542μg·mL-1. Poly I:C was mainly distributed in the liver, the spleen and the kidney of Poly I:C injected chickens.Residues of poly I:C in the chicken tissues Liquid scintillation counter quantitative assay of Poly I:C in the edible tissues of chickens was established to determine the maximum residue limit and the withdrawal time.30chickens were intramuscular injected Poly I:C at a dose of0.01mg/kg. Each time5chickens were sacrificed at the selected time intervals of4h,1d,2d,3d,4d,6d. The liquid scintillation counter was been used to detect the concentration of [3H]Poly I:C in the muscle, liver, fat, kidney of chickens. The results showed that after4h of injection the concentrations of Poly I:C in the edible chicken tissues were much lower than the safe tissue concentration (STC). It reveals that the withdrawal time of Poly I:C in chickens is0day. The concentration limit in liver and fat was0.01μg·g-1,0.02μg·g-1in kidney and muscle. The recovery of Poly I:C in muscle, fat,kidney and liver were97.97%±3.50%,99.78%±3.98%,96.12%±9.55%and94.50%±0.04%respectively.The precision of the method was between2.91%and9.03%.The squares of the correlation coefficients(r)for the standard curves were exceed0.99.